Canon EOS 1v rewinding velvia too early? Any ideas?

I just bought a 1v to replace my old one. If came with a functional battery.

It works great except it rewinds velvia rolls after 2 frames. I'm guessing these rolls might be bit stiffer than other rolls, which is triggering the rewind?

Im going to try a fresh battery in case this one is causing it, to help diagnose if its a fault.

however has anyone had this fault? Is it a known fault?

It came with a functional battery, but was the 1V professionally tested? No, not by the seller, but Canon?

I don't run much RVP through my never-fail 1N but it is possible the roll is at fault e.g. tension in the roll caused by sticking is sufficiently high to warrant the drive rewinding rather than risk tearing the film and, potentially, sending "schrapnel" into the shutter. Also install a power drive booster and 4/8 AA batteries; the 2CR5 is a lousy power source for this and a lot of other EOS bodies. Another thing to do is put the film in a changing bag and completely unwind it. Then rewind it into the canister. Not exactly fun, but doing this will establish if there is a point of resistance in the canister somewhere.

If several rolls of film repeat this problem, it may be the drive, but it sounds very far-fetched and would to me raise questions about the camera's past history. I have never had any sort of problem with my 1N, and others have 1V camera with likewise faultless operation. You can also do a system reset of the 1V pressing a combination of buttons behind the palm door.

It wasn't professionally tested. It's just a second hander I bought off a guy.

I have run a number of rolls through it to test, and all work well, however 50% of velvia rolls cause this issue. The velvia spindles feel a bit stiffer to pull out that other films, eg kodak tmax, so yes it appears the velvia is triggering the tension.

None of these velvia rolls cause any problem in other EOS cameras. I have pulled them out and rewound in darkroom and it doesnt seem a problem with the film.

I will try a new 2cr5. If it doesnt work I will get a refund, which the guy has offered. I am hoping the current battery is a just a bit weak, and that this is causing the camera to baulk and rewind early.

Does the battery-indicator indicate a full battery btw?

Never seen this on my 1v, I sometimes shoot it without the battery-grip/booster.

Battery indicator says full.

Tried brand new fresh battery and fault persists.

I will return it.

Thanks guys

How does that automated-stop feature works anyway?

I assume on the current drown by the motor.
Alternative would be a friction-clutch with a coupled switch.

The motor is worn and does not pull hard enough rolls that take somewhat more force to get the film out of the canister. A common fault of cameras with build in motors.

Thanks Zanxian

Hard to imagine for me that such motor is worn.

I shoot Velvia on my 1v sometimes- haven't seen this issue. However, in case there ever is a problem, I have my 1V set to leave the leader out when it rewinds. I know an experienced canon tech in south Florida- Isaac at Southern Photo Technical Support, whom you might reach out to if you keep it. He can usually service these cameras.